Rear tightener for safety ski binding

ABSTRACT

A boot-pushing member is rotatably mounted on an axle which extends transversely to the longitudinal axis of the ski and parallel to the tread of the ski and forms the web of a U-shaped member having legs which serve as pull rods and have free end portions which, on an axis that is parallel to the web, are pivoted to a plate which is secured to the ski. The boot-pushing member is subjected to the action of a spring, which produces the force for holding down the heel and the contact pressure between the toe portion of the skiing boot and a toe holder and which has one end that engages the axle which carries the boot-pushing member. The boot-pushing member is mounted on the axle by means of a slot and is slidable against the force of the spring so as to reduce the spacing of the sole-holding end of the boot-pushing member from the axle. The boot-pushing member has at least one laterally outwardly directed projection close to the sole-holding end, which projection serves to cooperate with a bracket, which extends inwardly from one leg of the U-shaped member, so that said bracket permits of a rotation of the boot-pushing member only when the sole-holding end has been displaced toward the axle. The sole-holding end lies over the straight line connecting the axle forming the web of the U-shaped member and the pivotal axis of the free end portions of the legs when the projection of the boot-pushing member engages the bracket from below.

United States Patent [7 2] Inventor Bernd Payrliammer Farchaut, Germany[21] Appl. No. 843,989 1 [22] Filed July 23, 1969 [45] Patented Oct. 12,1971 [73] Assignee l-lannes Marker Garmisch-Partenkirchen, Germany [32]Priority Mar. 7, 1969, May 9, 1969 [33] Germany [31] G 69 09 278.0-7402and P 1923 882:5

[54] REAR TIGHTENER FOR SAFETY SKI BINDING 9 Claims, 4 Drawing Figs.

I 52 us. c1 ..2s0/11. 35 T j 51 1111. c1 A63c 9/00 [50] Field of Search280/11.35

'HA, 11.35 T, 11.35 TA [56] References Cited UNITED STATES PATENTS3,249,365 5/1966 Beyl 280/11.35 HA 3,418,004 12/1968 Welker.... 280/11.35 HA 3,466,057 9/ 1969 Dobler 280/11.35 HA FOREIGN PATENTS 470,1905/1965 Switzerland 280/1 1.35 l-lA Primary Examiner-Benjamin HershAssistant Examiner-Robert R. Song Attorneys-Fleit, Gipple & Jacobson andStevens, Davis,

Miller & Mosher ABSTRACT: A boot-pushing member is rotatably mounted onan axle which extends transversely to the longitudinal axis of the skiand parallel to the tread of the ski and forms the web of a U-shapedmember having legs which serve as pull rods and have free end portionswhich, on an axis that is parallel to the web, are pivoted to a platewhich is secured to the ski. The boot-pushing member is subjected to theaction of a spring, which produces the force for holding down the heeland the contact pressure between the toe portion of the skiing boot anda toe holder and which has one end that engages the axle which carriesthe boot-pushing member. The boot-pushing member is mounted on the axleby means of a slot and is slidable against the force of the spring so asto reduce the spacing of the sole-holding end of the boot-pushing memberfrom the axle. The boot-pushing member has at least one laterally outwardly directed projection close to the sole-holding end, whichprojection serves to cooperate with a bracket, which extends inwardlyfrom one leg of the U-shaped member, so that said bracket permits of arotation of the boot-pushing member only when the sole-holding end hasbeen displaced toward the axle. The sole-holding end lies over thestraight line connecting the axle forming the web of the U-shaped memberand the pivotal axis of the free end portions of the legs when theprojection of the boot-pushing member engages the bracket from below.

PATENTEUum 12 um SHEET 10F 2 INVENTOR BERND PAYRHAMMER BY W Q ATTORNEYSPATENTEDUET 1 2 Ian SHEET 2 UF 2 6 l 2 560 lg 4 'NVENTO BERND PAYRHAMMERTORNEY REAR TIGHTENER FOR SAFETY SKI BINDING The present inventionrelates to a rear tightener for safety ski bindings, which tightenercomprises a boot-pushing member, which is rotatably mounted on an axlewhich extends transversely to the longitudinal axis of the ski andparallel to the tread of the ski and forms the web of a U-shaped memberhaving legs which serve as pull rods. The legs have free end portionswhich on an axis that is parallel to the web are pivoted to a platewhich is secured to the ski, the boot-pushing member being subjected tothe action of a spring, which produces the force for holding down theheel and the contact pressure between the toe portion of the skiing bootand a toe holder and which has one end that engages the axle whichcarries the boot-pushing member.

In a known rear tightener of that type, a prestressed helicalcompression spring is mounted in the boot-pushing member and through aninterposed plungerlike spring abutment acts on the axle, which isprovided adjacent to the spring abutment with a flat, which is disposedto be engaged by the spring abutment when the rear tightener is incondition for skiing whereas the spring abutment is forced against thenonflattened portion of the axle when the rear tightener is open. Whenthe rear tightener is in condition for skiing, the sole-holding portionof the boot-pushing member is thus under the action of a moment of forcewhich tends to retain the skiing boot on the ski. The boot-pushingmember can be pivotally moved to its open position under the action ofan opposing torque which exceeds the movement of force. When the springabutment has moved from the flat to the nonflattened portion of theaxle, virtually no efi'ort is required to swing the boot-pushing member.

This known rear tightener has various disadvantages by which its utilityis much reduced. It does not ensure a release exactly in response to apredetermined maximum force and an opposing torque which corresponds tothe moment of force is also required for an arbitrary opening of therear tightener. In the open condition of the device, a person touchingit may be injured because in this condition the spring is highlystrained and after a certain pivotal movement performed by thebootpushing member virtually under no effort the spring can relax tomove the boot-pushing member suddenly to its locking position.

For this reason, it is an object of the invention so to design a reartightener for safety ski bindings of the kind previously described thatis free of the disadvantages of the known rear tightener and is simplerand more reliable in operation than the latter and can be just aseconomically produced.

The invention relates to a rear tightener for safety ski bindings, whichtightener comprises a bootpushing member, which is rotatably mounted onan axle which extends transversely to the longitudinal axis of the skiand parallel to the tread of the ski and forms the web of a U-shapedmember having legs which serve as pull rods. The legs have free endportions which on an axis that is parallel to the web are pivoted to aplate which is secured to the ski. The boot-pushing member is subjectedto the action of a spring, which produces the force for holding down theheel and the contact pressure between the toe portion of the skiing bootand a toe holder and which has one end that engages the axle whichcarries the boot-pushing member. In such a rear tightener, the objectset forth above is accomplished in that the boot-pushing member ismounted on the axle by means of a slot and is slidable against the forceof the spring so as to reduce the spacing of the soleholding end of theboot-pushing member from the axle. The boot-pushing member has at leastone laterally outwardly directed projection close to the sole-holdingend which pro jection serves to cooperate with a bracket which extendsinwardly from one leg of the U-shaped member so that said bracketpermits a rotation of the boot-pushing member only when the sole-holdingend has been displaced toward the axle. The sole-holding end lies overthe straight line connecting the axle forming the web of the U-shapedmember and the pivotal axis of the free end portions of the legs whenthe projection of the boot-pushing member engages the bracket frombelow.

For reasons of design and strength, it is desirable to provide twoprojections on opposite sides of the boot-pushing member and to providetwo brackets on respective legs of the U- shaped member.

In a preferred embodiment of the rear tightener according to theinvention, the spring comprises a helical compression spring, which ismounted in a longitudinal bore, which opens into a slot and is providedwith a screw thread in its outer end portion and contains a screw plugserving as a spring abutment.

It has proved particularly desirable to provide an arrangement in whichthe boot-pushing member extends beyond its axle, the longitudinal boreextends into said extension, and said bore position contains a weakhelical compression spring, which bears at one end on the bottom of thebore and at the other end on the axle for the boot-pushing member. As aresult, the boot-pushing member will not be freely displaccable on theaxle when the rear tightener is in its open position.

Another disadvantage of the known rear tightener which has beenpreviously described is that it comprises no means for indicating thesettings of the force for holding down the heel and for the contactpressure so that there is an inevitable margin of uncertainty in thisrespect. This margin of uncertainty will be eliminated in the reartightener according to the invention if a spring abutment is provided atleast between the axle for the boot-pushing member and a spring and saidspring abutment forms an indicator of devices for indicating the settingof the force for holding down the heel and the contact pressure whereasthe scales of said devices are provided on the boot-pushing member.

In a development of this feature of the invention, each of the upper andlower walls of the boot-pushing member are suitably provided with a slotwhich extends in the direction in which the boot-pushing member isdisplaccable. The scales are provided at the longitudinal edges of saidslots and are relatively staggered in the longitudinal direction, andthe spring abutment comprises two diametrically opposite extensions,which serve as indicators. That indicating device which is the upper onewhen the rear tightener is in condition for use serves to indicate thecontact pressure. The other indicating device serving to indicate thesetting of the force for holding down the heel will be on top when theboot-pushing member has been pivotally moved to a position in which thescrew plug is easily accessible, e.g., by a screwdriver, so that it canbe screwed in or out to vary the force for holding down the heel.

To hold the boot-pushing member in position on the axle when the reartightener is in its open position, the axle may be provided with a flat,which is engaged by the weak helical compression spring, preferably witha spring abutment interposed.

An embodiment of the invention is shown by way of example on theaccompanying drawings, in which FIG. 1 is a top plan view showing therear tightener in condition for skiing.

FIG. 2 is a central longitudinal sectional view showing the reartightener of FIG. 1,

FIG. 3 shows the rear tightener of FIG. l with its boot-pushing memberswung out to the rear.

FIG. 4 is a side elevation showing the rear tightener in the sameposition as in FIG. 3 but partly cut open.

The rear tightener comprises two pull rods ll, 2, by which it is securedto the ski at a suitable heel plate, which is not shown because it isknown in various designs. The heel plate may be mounted, e.g., forlongitudinal adjustment on a bmeplate, which is secured to the ski. Thislongitudinal adjustment serves to adjust the rear tightener to skiingboots differing in size and to select the contact pressure applied bythe skiing boot against a toe holder.

At those ends which are not secured to the heel plate, the pull rods I,2 are interconnected by an axle 3, which is nonrotatably riveted inholes of the pull rods. On the axle, a bootpushing member 4 is mountedto be freely rotatable and iongitudinally slidable to a limited extent.For this purpose, the

member 4 has a slot 5. One end of the boot-pushing member constitutes asoleholder 6. As is apparent from FIGS. 2 and 4, the boot-pushing member4 has a blind hole 7, which is provided with a screw thread in its outerend portion. The blind hole 7 crosses the slot so that the axle 3extends transversely through the blind hole. A weak helical compressionspring 8 is disposed between the axle and the bottom of the blind holeand through an interposed spring abutment 9 bears on a flat formed onthe axle 3 (see FIG. 2). On the other side of the axle 3, the blind hole7 contains a strong helical compression spring 10, which bears on theaxle, also with a spring abutment ll interposed. At its other end, thisspring bears on a plug 12, which is threaded into the blind hole 7. Theouter end face of that plug is formed with a slot 13 for engagement by ascrewdriver. The spring abutment 11 comprises two extensions 14, 15,which are received by respective, diametrically opposite slots 16 or 17,which are formed in the boot-pushing member 4. That end of theboot-pushing member 4 which is not provided with the soleholder 6carries a cap 18, which serves at the same time as a handle.

Two oppositely disposed brackets 19, 20 having mirror symmetry aremounted on respective pull rods 1, 2 and adapted to cooperate withlateral projections 21, 22 of the boot-pushing member 4. As is apparentfrom H6. 1, the projections engage the brackets from below when the reartightener is in condition for use. A skiing boot is indicated indash-dot lines in FIGS. 1 and 2 to facilitate the understanding of therear tightener.

A rotation of the screw plug 12 causes a displacement of theboot-pushing member 4 on the axle 3 against the force of the helicalcompression spring 8, which is much weaker than the helical compressionspring 10. When the rear tightener is open, as is shown in FIG. 3 and 4,the desired resistance opposing a release and the desired force holdingdown the heel are thus adjusted. The extension 14 of the spring abutment11 extends into the slot 16 of the boot-pushing member 4 and serves asan indicator. A scale is provided at the longitudinal edges of the sloton the boot-pushing member 4 and may divide the range of adjustment intofour steps, as is indicated by way of example in FIG. 3.

When the skier has set the rear tightener to the desired resistanceopposing a release, he may step into the binding and may then checkwhether the correct pressure is applied by the rear tightener. Thischeck is accomplished by an indicating device, which consists of anextension of the spring abutment l1 and a scale provided on thelongitudinal edges of the slot 17 of the boot-pushing member 4 (see FIG.1). As to the division into steps, this scale is like the one providedon the other side of the boot-pushing member because the contactpressure should vary as a function of the resistance opposing a release.

To apply the binding, the skiing boot is first placed on the ski and isforced against the toe holder. The boot-pushing member 4 of the reartightener is then raised and its soleholder 6 is inserted into the heelgroove of the skiing boot and applied to the sole. The cap 18 at thefree end of the boot-pushing member is then swung down so that thespring 10 is stressed and the soleholder is moved to a position over thestraight line which connects the axle 3 and the pivotal axle connectingthe free end portions of the pull rods 1, 2 to the heel plate, notshown, and in this position is held by toggle joint action. In thiscondition, the projections 21, 22 of the boot-pushing member engage thebrackets 19, 20 of the pull rods and prevent a further rotation of theboot-pushing member. To get out of the binding it is sufficient to raisethe boot-pushing member so that the soleholder is disengaged from thesole of the skiing boot. This requires only a small effort, which neednot be sufficient to overcome the entire resistance opposing a release.

A safety release will be effected if the soldholder is subjected to theaction of an approximately vertically upwardly directed force which issufficient to stress the spring 10 and displace the boot-pushing member4 until the projections 21, 22 are no longer restrained by the brackets19, 20. The bootpushing member is then virtually freely rotatable and nolonger opposes a lifting of the heel of the skiing boot from the ski.The rear tightener is then ready to engage a boot. The flat formed onthe axle 3 and serving to hold the boot-pushing member in position whenthe rear tightener is open may be provided at a point other than shownin F IG. 2.

What is claimed is:

1. A ski boot rear heel tightener for safety ski bindings adapted to beused with a toe holder, said tightener comprising a U-shaped member,said U-shaped member comprising legs adapted to serve as pull rods andan axle connecting said legs, said axle forming the web of the U-shapedmember and extending transversely to the longitudinal axis of the ski, aboot-pushing member rotatably mounted on said axle, said boot-pushingmember defining a longitudinal bore and having a slot therethroughthrough which said axle extends, a spring positioned in saidboot-pushing member, said spring acting on said boot-pushing member toproduce a force for holding down the heel and contact pressure betweenthe toe portion of the ski boot and a toe holder, said spring having oneend that engages the axle which carries the boot-pushing member, saidboot-pushing member being slidable against the force of said spring soas to reduce the spacing of the sole-holding end of the boot-pushingmember from the axle, at least one outwardly directed projection securedto said boot-pushing member, bracket means connected to said legs, saidbracket means extending inwardly from said legs to cooperate with eachsaid outwardly directed projection so that said bracket means permits arotation of said boot-pushing member only when the said sole-holding endhas been displaced towards the axle, said sole-holding end lying overthe straight line connecting the axle forming the web of the U-shapedmember when the outwardly directed projection of said boot-pushingmember engages said bracket means from below.

2. A rear heel tightener according to claim 1, wherein two laterallyoutwardly projections are provided on opposite sides of saidboot-pushing member and two brackets are provided on the respective legsof said U-shaped member.

3. A rear heel tightener according to claim 1, wherein the spring is ahelical compression spring, said helical compression spring beingmounted in said longitudinal bore, said lon gitudinal bore beingprovided with a screw thread at least in its outer end portion toreceive a screw plug, said screw plug serving as a spring abutment.

4. A rear heel tightener according to claim 3, wherein the boot-pushingmember extends beyond the axle and the longitudinal bore portioncontains a weak helical compression spring, said weak helicalcompression spring bearing at one end on the bottom of said bore and atthe other end on said axle for the boot-pushing member.

5. A rear heel tightener according to claim 4, wherein a spring abutmentis provided at least between the axle for the boot-pushing member and aspring.

6. A rear heel tightener according to claim 5, wherein said springabutment forms an indicator means, said indicator means being adapted toinclude the settings of the force for holding down the heel and thecontact pressure, and registering the settings on scales provided onsaid boot-pushing member.

7. A rear heel tightener according to claim 1, wherein said boot-pushingmember comprises a housing, slot means defined by said housing, scaleindicia provided on said housing, said scale indicia positioned adjacentthe longitudinal edge of said slot means in a substantially staggeredarrangement, and a spring abutment mounted in said housing, said springabutment comprising two diametrically opposed extensions which serve asindicators.

8. A rear heel tightener according to claim 4, wherein the axle isprovided with a flat, a weak helical compression spring engaging saidaxle and an abutment interposed between said axle and said helicalspring when said rear tightener is in an open condition to hold theboot-pushing member in position on the axle.

9. A rear heel tightener according to claim 1, wherein said legs havefree end portions pivoted to a plate, said pivoted free.

end portions being on an axis parallel to said axle.

1. A ski boot rear heel tightener for safety ski bindings adapted to beused with a toe holder, said tightener comprising a U-shaped member,said U-shaped member comprising legs adapted to serve as pull rods andan axle connecting said legs, said axle forming the web of the U-shapedmember and extending transversely to the longitudinal axis of the ski, aboot-pushing member rotatably mounted on said axle, said boot-pushingmember defining a longitudinal bore and having a slot therethroughthrough which said axle extends, a spring positioned in saidboot-pushing member, said spring acting on said boot-pushing member toproduce a force for holding down the heel and contact pressure betweenthe toe portion of the ski boot and a toe holder, said spring having oneend that engages the axle which carRies the bootpushing member, saidboot-pushing member being slidable against the force of said spring soas to reduce the spacing of the soleholding end of the boot-pushingmember from the axle, at least one outwardly directed projection securedto said boot-pushing member, bracket means connected to said legs, saidbracket means extending inwardly from said legs to cooperate with eachsaid outwardly directed projection so that said bracket means permits arotation of said boot-pushing member only when the said soleholding endhas been displaced towards the axle, said soleholding end lying over thestraight line connecting the axle forming the web of the U-shaped memberwhen the outwardly directed projection of said boot-pushing memberengages said bracket means from below.
 2. A rear heel tighteneraccording to claim 1, wherein two laterally outwardly projections areprovided on opposite sides of said boot-pushing member and two bracketsare provided on the respective legs of said U-shaped member.
 3. A rearheel tightener according to claim 1, wherein the spring is a helicalcompression spring, said helical compression spring being mounted insaid longitudinal bore, said longitudinal bore being provided with ascrew thread at least in its outer end portion to receive a screw plug,said screw plug serving as a spring abutment.
 4. A rear heel tighteneraccording to claim 3, wherein the boot-pushing member extends beyond theaxle and the longitudinal bore portion contains a weak helicalcompression spring, said weak helical compression spring bearing at oneend on the bottom of said bore and at the other end on said axle for theboot-pushing member.
 5. A rear heel tightener according to claim 4,wherein a spring abutment is provided at least between the axle for theboot-pushing member and a spring.
 6. A rear heel tightener according toclaim 5, wherein said spring abutment forms an indicator means, saidindicator means being adapted to include the settings of the force forholding down the heel and the contact pressure, and registering thesettings on scales provided on said boot-pushing member.
 7. A rear heeltightener according to claim 1, wherein said boot-pushing membercomprises a housing, slot means defined by said housing, scale indiciaprovided on said housing, said scale indicia positioned adjacent thelongitudinal edge of said slot means in a substantially staggeredarrangement, and a spring abutment mounted in said housing, said springabutment comprising two diametrically opposed extensions which serve asindicators.
 8. A rear heel tightener according to claim 4, wherein theaxle is provided with a flat, a weak helical compression spring engagingsaid axle and an abutment interposed between said axle and said helicalspring when said rear tightener is in an open condition to hold theboot-pushing member in position on the axle.
 9. A rear heel tighteneraccording to claim 1, wherein said legs have free end portions pivotedto a plate, said pivoted free end portions being on an axis parallel tosaid axle.